Cetek Corporation

Waters Associates, Inc.

Thar Instruments, Inc.

Waters Technologies Corporation

James L Waters

Dallas E Hughes

Yuriy M Dunayevskiy

Louis Abrahams

Burleigh M Hutchins, Jr

Barry L Karger

Kimber D Fogelman

Lalit M Chordia

Edwin E Wikfors

Herbert J Hedberg

Brian A Kangas

Edwin E Wickfors

Lalit Chordia

A splitter for a pressurized primary flowstream of a mobile phase is provided. The splitter comprises a first splitting stage that divides the primary flowstream between a major split flowstream and a minor split flowstream by means of a first and a second restrictive flow element; a first dilution stage that combines a dilution flow source with the minor split flowstream to create a diluted minor flowstream; a second splitting stage that divides the diluted minor flowstream between a secondary major diluted flowstream and a secondary minor diluted flowstream by means of a third restrictive element in the secondary minor diluted flow stream; and a second dilution stage wherein a conditioning flow source conditions the secondary minor diluted flow stream after the third restrictive element prior to outlet of the secondary minor diluted flowstream from the splitter.

Variable ratio flow splitter for a flowstream

The invention is directed to a high throughput capillary electrophoresis (CE) system, which comprises multiple mobile CE detector modules that are transportable by a programmable fluid-handling arm assembly to fixed samples in microtiter plate wells for analysis. The CE system of the invention is capable of simultaneously automating sample preparation and multiple CE analysis of the sample in a continuous timely process. The CE detector modules of the invention may be equipped with any suitable detection method, such as an ultraviolet (UV) absorbance or a laser-induced fluorescence (LIF) detector.

High throughput capillary electrophoresis system

The invention relates to capillary electrophoretic methods for detecting ligands or hit compounds that can bind to a selected target at or above a selected binding strength. The method allows one to rank various ligands based on their relative affinity, i.e., the relative stability of the target/ligand complex during capillary electrophoresis under selected conditions. The method also enables selective detection of strong-to-moderate binding hit compounds, even in the presence of high concentrations of weaker, competitive hit compounds.

Capillary electrophoretic method to detect target-binding ligands and to determine their relative affinities

This invention combines a capillary electrophoresis (CE) technique for screening complex biological samples with mass spectrometry (MS), to provide a streamlined procedure for identifying and characterizing candidate ligands in a complex biological sample that bind at a selected binding strength to a selected target molecule. The method of the invention advantageously identifies and characterizes tight-binding ligands when high concentrations of weak ligands are present in the sample, which may mask lower concentrations of tight-binding ligands in the sample. The method involves interfacing a capillary from a CE instrument with a post-capillary mass spectrometer to provide direct mass analysis of target/ligand complexes that migrate stably through the CE instrument. All weaker-binding ligands will not be detected during the MS analysis because they dissociate from the target early during the CE run, before reaching and entering the mass spectrometer. Therefore, this method can identify and structurally characterize moderate-to-tight-binding ligands in complex biological samples, even in the presence of high concentrations of weak-binding ligands.

Method to detect and analyze tight-binding ligands in complex biological samples using capillary electrophoresis and mass spectrometry

This invention relates to a competitive-binding, capillary electrophoretic method of detecting new therapeutic regulatory (modulating) and diagnostic compounds in natural samples and other complex biological materials. The present method generally comprises mixing a preselected, detectable target with a sample of complex biological material to produce a first, sample/target mixture capillary electrophoresis apparatus. Subsequently, the first mixture is mixed with a pre-selected, tight-binding competitive ligand (TBCL), prior to produce a second, sample/target/TBCL mixture, for a predetermined optional incubation period sufficient to allow the TBCL to bind a pre-selected percentage of the available target in the absence of any other ligand. An aliquot of the second mixture is subsequently subjected to pre-optimized capillary electrophoresis, during which the migration of the target is monitored. The presence of a potential new compound is indicated by the increase in the peak area of the unbound target peak and/or decrease in the peak area of the TBCL/target complex peak. A capillary electrophoretic profile of the second mixture is produced, which may be compared to a reference standard. The reference standard typically comprises a capillary electrophoretic profile or migration pattern of the target when mixed with a TBCL in an absence of any other competing ligand under similar, pre-selected capillary electrophoretic conditions.

Capillary electrophoretic methods to detect new biologically active compounds in complex biological material

A compact pumping system especially useful in liquid chromatography wherein comprising a liquid path which is fully flushed in each stroke of a pump, a pump which provides substantially pulse-free flow, a pressure-sensor integrated into said flow path and operably connected to the control circuit of a bifilar stepping motor. This circuit is so designed that the driving current applied to the motor is only that required to pump the liquid. The avoiding of heat associated with a greater current is particularly important in forming a compact package of motor and pump for use in liquid chromatography.

Pumping apparatus

A compact pumping system especially useful in liquid chromatography wherein comprising a liquid path which is fully flushed on each stroke of a pump, a pump which provides substantially pulse-free flow, a pressure-sensor integrated into said flow path and operably connected to the control circuit of a bifilar stepping motor. This circuit is so designed that the driving current applied to the motor is only that required to pump the liquid. The avoiding of heat associated with a greater current is particularly important in forming a compact package of motor and pump for use in liquid chromatography.

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Framingham, MA, United States of America

James L Waters